I have a pair of A. chrysopterus in an H. crispa in a 150 with a pair of A. nigripes and H. magnifica. The aquascaping was done such that they have their own territories on each side of the tank, with a rock hill in the middle. Occasionally the chrys' come over to bully, but the 'gripes hold their ground and it always ends quick and easy. Been together for over 2 years. The chrys' spawn regularly. It can be done. Start with small specimens. And lesser known aggressive species (if there is such a thing with clowns). Good luck.
Dan